Complex Analysis: Properties of Line Integrals

[tarheelborn]

Homework Statement

Demonstrate that $$\int_{-\gamma} f(z)|dz|=\int_{\gamma} f(z)|dz|$$ where $$\gamma$$ is a piecewise smooth path and f is a function that is continuous on $$|\gamma|$$.

Homework Equations

The Attempt at a Solution

This proof seems like it should be very simple, but I am not sure it is really saying that it's just turning a path around to go in the opposite direction. Could someone please help me out? Thanks.

 

[HallsofIvy]

Consider the substitution u= -z.